Dead-end alleys shall be avoided wherever possible but, if unavoidable, shall be provided with adequate turnaround facilities at the dead end. Alley intersections and sharp changes in direction shall be avoided but, where they are necessary, corners shall be cut off sufficiently to permit safe vehicular movement. Alley right-of-way width shall be not less than twenty-five feet in commercial or industrial zones. Except as otherwise provided in this title, alleys shall follow the general standards governing streets.